The concept of nirvana occupies a unique place in Buddhist thought—not just because it represents the culmination of the Buddhist path, and not just because it represents the nicest imaginable place to be, but also because of the way it straddles the two sides of Buddhism.
There is, on the one hand, the naturalistic side of Buddhism, featuring ideas that would fit easily into a college psychology or philosophy course: ideas about the nature of the mind, about the causes of human suffering, and about how we should live our lives in light of these realities. These are the ideas that form the core of the ‘secular Buddhism’ that is practiced by many in the West. Indeed, so naturalistic, so ‘secular’, is this set of ideas that some people see Buddhist meditation as more of a therapeutic than a spiritual undertaking, as basically palliative and not too profound. That’s a particularly common view of the kind of Buddhist meditation known as mindfulness meditation—which is sometimes packaged in the frankly therapeutic form of ‘mindfulness-based stress reduction’.